1. Field of the Invention
This invention relates in general to seat belts for motor vehicles, and in particular to a device for adjusting the shoulder portion of a seat belt.
2. Description of the Prior Art
Most motor vehicle seat belts currently installed have an outboard portion, which is located closer to the vehicle side windows, and an inboard portion, which is located in the central portion of the vehicle. The outboard portion includes a belt or web and a latchplate which slides on the web. The outboard portion secures to a retracting mechanism, extends over a web guide mounted to a vehicle frame post and then back to an anchor. The inboard portion comprises a web with a buckle on the end, the web being anchored to the floor of the vehicle. The latchplate latches into the buckle.
When the occupant grasps the latch plate and draws it over and snaps it into the buckle, the resulting configuration will define a lap portion that extends across the lap of the user, and a shoulder portion that extends diagonally upward to the web guide.
While this arrangement works successfully for adults, the shoulder portion will be too high for small children. The angle of inclination of the shoulder portion is determined by the position of the web guide. In many vehicles, the web guide is fixed in place and set for adults. Other vehicles allow some vertical adjustment of the web guide, but not much. In many cases, the belt will pass in front of the child's face or neck. This is not a good position for protecting the child. Moreover, the child may place the belt shoulder portion behind him, eliminating protection other than the lap portion of the belt.
One device marketed comprises a sleeve that snaps over part of the lap and shoulder portions. The sleeve will reposition the point at which the shoulder portion extends from the lap portion. This repositioning changes the angle of the shoulder portion so as to pass across the shoulder of a child. However, the sleeve is not adjustable for different sizes of children. Also, once installed, an adult sitting in that place would have to remove the sleeve in order to use the seat belt properly.
Another device marketed as a seat belt adjuster comprises a two-piece plastic clip which clips over the lap portion. The clip has a tongue or lug on the front side which extends downward, defining a slot. The user places the shoulder portion in the slot under the tongue, changing the inclination of the shoulder portion. The tongue will not lock the clip in place. Also, the clip would appear to break in the event of a moderate collision.